Decided it was a good time to figure out exactly how the IBBS Backup Battery will integrate with the Garmin avionics, especially since I keep seeing references to POWER 2 in the Garmin DOC.
Fortunately, both Garmin and TCW provide excellent documentation. I had previously allocated a CB for the main power to the IBBS, but failed to provide for the CB needed for the trickle power. Decided to locate the always on trickle power CB next to the always on CB's for the USB ports for the pilot and pass positions.
Used template to locate the Trickle CB from the back side of the right sub panel, final sized with unibit. The buss bar for this will always be hot.